Universitat de Barcelona
Now showing items 1-20 of 22
The aim of this dissertation is to present some new results on stochastic analysis. It consists on three works that deal with two Gaussian processes: the Brownian motion and the fractional Brownian motion with Hurst parameter ...
The present dissertation is a contribution to the field of Mathematical Logic and, more particularly, to the subfield of Set Theory. Within Set theory, we are mainly concerned with the interactions between the largecardinal ...
This thesis deals with the jet transport for numerical integrators and the effective invariant object computation of delay differential equations. Firstly we study how automatic differentiation (AD) affects when ...
[eng] Many times machine learning is casted as an optimization problem. This is the case when an objective function assesses the success of an agent in a certain task and hence, learning is accomplished by optimizing that ...
The representation (or feature) learning has been an emerging concept in the last years, since it collects a set of techniques that are present in any theoretical or practical methodology referring to artificial intelligence. ...
En esta tesis se estudian problemas relacionados con acciones de grupos finitos en 4-variedades diferenciables y simplécticas. Se prueba que toda 4-variedad diferenciable cerrada X admite una constante C>0 tal que cualquier ...
The theory of Bergman spaces has been a central subject of study in complex analysis during the past decades. The book [7] by S. Bergman contains the first systematic treat-ment of the Hilbert space of square integrable ...
En esta tesis abordamos el problema de la aproximación de anillos locales por anillos de Gorenstein en el caso cero-dimensional. Nos centramos en el estudio y el cálculo efectivo de la colongitud de Gorenstein, una noción ...
The main goal of this work is to study vector-valued Bergman spaces and to obtain the weak factorization of these spaces. In order to do that we need to study small Hankel operators with operator-valued holomorphic symbols. ...
In the thesis we consider higher regularity of the free boundaries in different variations of the obstacle problem, that is, when the Laplace operator b. is replaced with another elliptic or parabolic operator. In the ...
We develop criteria for hitting probabilities of Gaussian random fields with associated canonical metric given by a class of gauge functions. This yields upper and lower bounds in terms of general notions of Hausdorff ...
This dissertation is devoted to the analysis of the motion of small bodies, like asteroids, in the neighbourhood of the Earth-Moon system from a celestial mechanics approach. This is an extensive area of research where ...
Aquesta tesi té dos objectius. El primer és contribuir en la teoria de congruències entre formes modulars via representacions de Galois. El segon és resoldre nous problemes diofantins de tipus Fermat. En quant a representacions ...
In the central part of this thesis we study for different interpretability logics the following aspects: completeness for modal semantics, decidability and algorithmic complexity. In particular, we will study two basic ...
In this thesis, an option price decomposition for local and stochastic volatility jump diffusion models is studied. On the one hand, we generalise and extend the Alòs decomposition to be used in a wide variety of models ...
A dynamical system is one that evolves with time. This definition is so diffuse that seems to be completely useless, however, gives a good insight of the vast range of applicability of this field of Mathematics has. It is ...
El teorema de equidistribución de Bilu establece que, dada una sucesión estricta de puntos en el toro algebraico N-dimensional cuya altura de Weil tiende a cero, las órbitas de Galois de los puntos se equidistribuyen con ...
A remarkable result in Harmonic Analysis is the so-called Rubio de Francia’s extrapolation theorem. Roughly speaking, it says that if one has an operator T that is bounded on Lp(v), for some p 1 and every weight v in Ap, ...
Complex systems can be understood as an entity composed by a large number of interactive elements whose emergent global behaviour cannot be derived from the local laws characterizing their constituents. The observables ...
This dissertation is devoted to developing modal logical tools that can be used in the field of proof theory and ordinal analysis. More precisely, we focus on the relation between strictly positive modal logics and both ...
